The invention relates to power-driven conveyors and, more particularly, to a conveyor using a conveyor belt with obliquely oriented rollers to accumulate and move articles laterally across the conveyor.
Many material-handling applications require that conveyed articles be accumulated and aligned single file or arranged in groups for downstream processing or inspection. One way to arrange articles single file against a side of the conveyor is with a conveyor belt having rollers with salient portions that extend beyond top and bottom surfaces of the belt. The rollers roll on supporting bearing surfaces beneath the bottom surface of the belt as it advances in a direction of belt travel. The rollers are arranged to rotate on axles oblique to the direction of belt travel. The rotation of the rollers on their oblique axles provides a sidewise component of force directing conveyed articles atop the rollers toward a side guide flanking the belt. But, because contact between the rollers and the bearing surface is not frictionless, roller wear accelerates and belt tension increases. Furthermore, because the rotation of the oblique rollers pushes the articles forward as well, accumulated articles would experience high back line pressure. Consequently, such a conveyor has shortcomings in applications requiring accumulation of articles in a single file or side by side.